Foams are often encountered in circumstances where their presence is not desired, and the prevention or reduction of the formation of foam is important for many applications. Thus a variety of foam-inhibiting and defoaming agents have been developed.
Foams may be caused by e.g. surfactants, proteins, fats and biocides. Different defoamers are normally required to obtain an efficient defoaming for each of the substance classes. An especially difficult type of composition to defoam is a composition comprising the biocide N,N-bis(3-aminopropyl)dodecylamine.
Propoxylates of aliphatic alcohols have earlier been used as defoaming agents.
DE 3018173 relates to highly alkaline, storage stable, and low-foaming solid cleaning compositions comprising a branched C12-022 alcohol based detergent with 5-15 PO units. An especially preferred product was stated to be C16 Guerbet alcohol reacted with 10 moles of propylene oxide.
US 2005/0215452 relates to the use of a 010 alkanol alkoxylate mixture as emulsifier, foam regulator and wetting agent. Specifically 2-propylheptanol propoxylates with up to 1.71 PO are disclosed, though products including both PO and EO units are preferred.